<script>

    function add(){
        number++;
    }
    function sub(){
        number--;
    }
</script>

<template>
<h1>功德+{{number}}</h1>
    <br>
    <div id="bt1" @click="add">功德+1</div>
    <div id="bt2" @click="sub">功德-1</div>
</template>

<style>

</style>